UNIX-Related Books
While there is some information about 80s/90s UNIX available online (usually archives from Usenet), there is a ton of information available in physical printed books of the day. I’ve been amassing a collection of various UNIX-related books so I can learn as much as possible about UNIX and the machines it ran on during the 80s/90s.
Managing NFS and NIS lex & yacc LaTeX For Everyone Mastering SunOS